1. SC 2004 GEWiTTS – GRID Enabled Wind Tunnel Test Service

2. SC 2004 Outline The GEWiTTS project Manchester University Transonic Wind Tunnel and PSP system GEWiTTS software architecture Firewalls

3. SC 2004 GEWiTTS Vision: Authenticated collaborative synergy between computational and experimental facilities GRID Enabled Wind Tunnel Test Service –Aim: Remote operation of wind tunnel data acquisition systems in a collaborative, virtual organisational environment –PSP system used as a vehicle that supports high data rates, adaptability and remote processing of results Addressing issues of:- –Remote collaborative control of experiments –Safety critical systems –Data confidentiality (https:) –Authentication –Firewalls Project partners –BAE Systems Advanced Technology Centre –BAE SYSTEMS (Warton) Air Systems –Manchester Uni –ARA

4. SC 2004 Manchester University TWT -Suck-down tunnel -M = 0.3-0.8 -1 minute runtime -15 minutes duty cycle -Hazardous environment

5. SC 2004 Beam Steering Mirrors LASER Polymer and dye Substrate Organic dye dissolved in gas permeable polymer absorbs green photons Re-radiates at longer wavelength Oxygen molecules in the polymer can quench this process Relationship between emitted photons and air pressure Real time data msec & sec timescales Configurable on-the-fly Equivalent to computational steering High data rates Class IV laser

6. SC 2004 Chemistry Stuff Metalloporphyrins Visible wavelength absorption bands - 532nm coincides with freq doubled Nd:Yag Useful (easily measurable) phosphorescence- 650nm Platinum meso-Tetra-(pentafluorophenyl) porphine, Pt(TfPP). Siloxane polymer - rubbery coating, 20-30 m thick, high gas permeability Permeability = ƒ(T)

7. SC 2004 Decay Lifetime Measurement System Return signal is close to an exponential independent of initial excitation no paint thickness/uniformity effects no sensitivity to surface curvature dye concentration or uniformity has little effect ambient light levels are irrelevant Reference image/measurement not required Application to high data rates Sufficient data for simultaneous two variable extraction (P+T)

8. SC 2004 ARA Wind Tunnel Tests Large Transonic Wind tunnel In UK Fully automatic operation Data on-line within 5-ish seconds Edge detection routines used for model location

9. SC 2004 Approximate area covered by zoomed scan below Bracket Upper Surface Tailplane at M=0.8, 10 o

10. SC 2004 Client 1 Client n Wind tunnel 1 Wind tunnel n GEWiTTS scenario

11. SC 2004 GEWiTTS software Servers –PSP system server Can support multiple clients –Tunnel Control System server –Interlocks Client –Can support multiple servers –Performs processing and display of results Management application –Health & Safety –Security –Validation –Collaborative working process Portal – real time

12. SC 2004 List of experimental sessions being run at the facility List of clients taking part in each session and the controller of the experiment List of PSP servers in each session Interface with tunnel control system Video output to clients

13. SC 2004 List of active sessions Status of client Client interface

14. SC 2004 Lessons learned(1) Collaborative working –Overall control of experiment rests with facility operator (H&S concerns) –Partial control can be delegated –SessionManager (or portal) is tightly bound to facility –Very similar to the dynamics of a meeting –Designation of experiment leaders and viewers is critical –Access is granted and validated on a session-by-session basis –A separate dialogue application (a chatter example) is vital –Good visual feedback on application status is essential in real time applications

15. SC 2004 Lessons learned(2) User or client validation –Essential –User ID must propagate through audit trail Certificates allow single sign-on use-anywhere Are usually not time-bound –Solution is to generate unique ID at use time Fingerprint ID allows access to.exe created for that user only Timestamps Fingerprint ID Browser Compile client.exe Database HTTPS

16. SC 2004 Firewalls and other irritations BAE Systems and its partners operate strict firewall policies –Traversing multiple firewalls is a difficult but unavoidable task –Connections can only be initiated on http or https –Security and user validation is essential Export licenses –Remote execution of code and data traversing international boundaries create specific problems ISO9001/2 –Audit trails – confidence that repeat computations give identical results

17. SC 2004 Summary PSP system and a wind tunnel can be operated remotely in a real-time multi-user collaborative working scenario for integration within the CFD driven design process Dynamics of a collaborative working environment mimic those of a traditional meeting, and software has been developed to reflect this